The two African American friends from Harlem, New York fell into a respectful silence, to hear President Barack Obama, whose familiar baritone barely carried to where they were.

But sitting at the foot of the Washington Monument, where the 1963 march started, ending with King’s speech at the Lincoln Memorial, they sounded disappointed, yet hopeful.

President Obama captured it aptly in his speech, which, he later explained, tried not to either match or upstage King’s, one of the two greatest speeches in history, according to him.

The other, he didn’t say, would be Lincoln’s at Gettysburg.

King’s speech in 1963, at the culmination of the March on Washington by an estimated 250,000 people, led shortly to laws ending segregation and guaranteeing equal voting rights.

But race relations remain contentious, manifesting most recently in the trial, and acquittal, of a White Hispanic man in the case of the death of an African American teenager.

Some like Jones argue not much has changed.

President Obama disagrees. He said these skeptics dishonour “the courage and the sacrifice of those who paid the price to march in those years”.

But, the president added, it would also be a dishonour to these men and women if someone were to “suggest that the work of this nation is somehow complete”.

“For what does it profit a man, Dr King would ask, to sit at an integrated lunch counter if he can’t afford the meal?”

He said a little later: “And so as we mark this anniversary, we must remind ourselves that the measure of progress for those who marched 50 years ago was not merely how many blacks could join the ranks of millionaires. It was whether this country would admit all people who are willing to work hard regardless of race into the ranks of a middle-class life.”

Jones turned to her friend with a triumphant look: “I could have written that speech for him.” Only, her version would have been far more dismal and worrying than Obama’s.